1. Field of the Invention
The present invention relates to a light emitting display and a method of driving thereof.
2. Description of the Related Art
Recently, there have been developed various flat panel displays that can reduce heavy weight and large bulk that is a disadvantage of a cathode ray tube display.
The flat panel displays include a liquid crystal display (hereinafter, referred to as a “LCD”), a field emission display (FED), a plasma display panel (hereinafter, referred to as a “PDP”), an electro-luminescence (hereinafter, referred to as an “EL”) display or light emitting display, etc.
The light emitting displays are largely classified into an inorganic light emitting display (hereinafter, referred to as an “LED”) and an organic light emitting display (hereinafter, referred to as an “OLED”) depending on a material of a light emitting layer. Light emitting displays have a fast response speed and high light emitting efficiency, brightness, and broad viewing angle as a self-luminant element. An organic light emitting display (OLED) has advantages of a low DC driving voltage, uniformity of emitted light, easy pattern formation, good light emitting efficiency in comparison with other light emitting elements, all color emission in a visible region, etc.
Furthermore, the organic light emitting diode (OLED) is classified into a passive matrix organic light emitting display (PMOLED) and an active matrix organic light emitting display (AMOLED) depending on a driving method.
FIG. 1 is a circuit diagram illustrating a part of a related art active matrix organic light emitting display.
As illustrated in FIG. 1, the related art active matrix organic light emitting display 100 is largely divided into a driving unit 102, a light emitting unit 104 and a voltage source VDD.
Specifically, the driving unit 102 of the related art active matrix organic light emitting display 100 is electrically connected to a data line 106 and a scan line 108. The light emitting unit 104 includes one light emitting diode that emits a specific color light. The light emitting unit 104 is driven by one driving unit 102.
The voltage source VDD supplies the same voltage to the light emitting units 104 of all pixels. The same voltage should be satisfied with the light emitting units, which have low emitting efficiency. Therefore, because the light emitting units of high emitting efficiency are supplied unnecessarily high voltages, power consumption is increased and the driving transistor 102 is deteriorated, so a lifetime of the OLED is reduced.